الفهرس 
First Generation Solar CellsOnly 14 pages are availabe for public view
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Abstract
Increasing worldwide demand for energy and limited fossil fuels reserves on the planet require development of reliable and renewable energy sources. Among the various technologies available nowadays, photovoltaic is believed to be one of the cleanest ways in achieving this goals. But the high cost of manufacturing solar cells was the main reason behind the non widespread of these cells and used as a substitute of traditional sources. The Dye Sensitized Solar Cell (DSSC) based on titanium dioxide plays a major role in the future of solar energy due to the high efficiencies and good long-term stability. Dye Sensitized Solar cell (DSSC) belongs to the group of thin film solar cells. The DSSC consists of four main components [1] , the photoelectrode, the dye, the electrolyte (redox), and the counter electrode. All of these constituents are collected in a sandwich configuration between two conducting glass slides, with the redox filling the free space in between. In this ongoing study, different components and ambient process conditions for the fabrication were investigated. Different chemical treatments were also explored towards optimizing the cell performance. According to the importance of the sensitizing dye role ,a group of natural and organic dyes were evaluated. A Comparison between the natural and organic dyes and explanation for their roles is discussed. There are efforts made to introduce polymers into solar cells to replace its components hoping for low coast , ease processing, better efficiency and long life time. Replacing liquid electrolyte in dye sensitized solar cells to solve drawback for long-term practical operation due to electrolyte leakage or evaporation, and also makes large-scale production difficult. Different polymer electrolytes were employed in different forms (gel and thin film). An increase in efficiency happened with the polymer electrolyte due to the ionic conductivity. Different natural dyes were extracted from different flowers (hibiscus, rose and black berry). Black berry sensitized solar cell gave the best efficiency. We employed the polymer electrolyte in the black berry sensitized solar cell leading to efficiency 2.4%. Also, organic dye Di-tetrabutylammonium cis-bis (isothiocyanato) bis (2,2’-bipyridyl-4,4’dicarboxylato) ruthenium (N719) has been used to sensitize the TiO2. N719 sensitized solar cell with polymer electrolyte leading to efficiency 8%. An explanation of the ionic conductivity is discussed. The polymer used as a host matrix for the ions caging the cation and freeing the anion that used to regenerate the dye. Different polymers with different function groups have different electron affinity with the cation. Standard solar cell characterization techniques such as current-voltage and spectral response measurements under simulated sun light of intensity 100 mW\cm2 and 1.5 AM were employed to evaluate the cell performance. FTIR is used to investigate the polymer electrolyte. Conductivity meter were employed to measure the ionic conductivity of the different polymer electrolytes.